Electric-lamp socket.



No. 693,738. Patented Feb. I8, I902.

J. D. PIERCE.

ELECTRIC LA'MP SOCKET.

[Application filed Ian. 4, 1901.)

(No Model.)

UNTTEE STATES PATENT @EETEE.

JOHN D. PIERCE, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC-LAMP SOCKET.

5PEGEEIGATION forming part of Letters Eatent No. 693,738, dated February 18, 1902.

Application filed January 4-, 1901. Serial No. 42,126. (No model.)

To a. whom it may concern.-

Be it known that 1, JOHN D. PIERCE, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Electric-Lamp Sockets, of

which the following is a specification.

The object of my invention is to so con struct an electric-lamp socket as to reduce the number of parts to a minim um withoutim pairing the efliciency of the structure, thereby reducing size and cost, to render the structure neat in external appearance,and to facilitate the work of the electrician in making connections. This obj ectI attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 is a top or plan view of my improved electric-lamp socket. Fig. 2 is a transverse section of the same on the liner: a, Fig. l. Fig. 3 is a transverse section on the line b b, Fig. 1, with outer casing. Fig. 4 is a perspective view of the threaded shell of the socket. Fig. 5 is a sectional view illustrating the method of fitting together the two parts of the socket,'and Fig. 6 is a view of a modification of the invention.

The socket comprises two main parts, the threaded metallic shell 1 and the base-b1ock 2, the latter being composed of porcelain or other non-conducting material and having in one side a recess 3, to which is adapted an inwardly-bent flange 1 at one side of the top of the shell 1, the opposite side of said shell having an inwardly-extending flange 5, which is adapted to bear against the under side of a recessed portion of the block 2 and is confined thereto by' anut 7 on a screw 6, the latter passing through an opening in the block and having above the latter a head, between which and the upper face of the block is interposed the bent or hooked end of one of the wires, whereby current is conveyed to the lamp, this wire being therefore in electrical connection with the shell 1.

The under side of the block 2 is recessed transversely for the reception of a springfinger 8, which makes contact with the central terminal on the head of the lamp, said spring-finger being held in place by means of a screw 9, which passes through an opening in the block 2 and has a head which serves to confine to the top of said block the other electrical conducting-wire. A lug 10 on the top of the block 2 is interposed between the heads of the screws 6 and 9, so as to effectually insulate one from the other.

In fitting the threaded shell 1 to the baseblock 2 of the socket the parts are held at an angle to each other, as shown in Fig. 5, so that the flange 4 of the shell can be slipped into the recess 3 of the base-block, the shell beingthen swung in the direction of the arrow, so as to bring its flange 5 into contact with the recessed under face of the block, to which it is secured by means of the screw 6 and nut 7, this single screw and nut thus serving not only to secure the two parts of the socket together, but also acting as a binding-post for one of the electrical conductors of the socket. The other screw 9 also performs the double duty of securing in place the spring-finger 8 and serving as a binding-post for the other conductor of the socket. Hence the latter can be very cheaply made, as it comprises but a minimum of parts, each of simple construction, said parts being capable of being readily fitted together or taken apart.

It is manifest that the nut 7 might, if desired, be located on the upper side of the block 2 instead of upon the under side of the same, and the screw 9 might be inserted from the inside of the socket and have a similar external nut; but the construction shown is preferred, because of its greater convenience.

The adaptation of the spring-finger 8 to the transverse groove or slot in the under side of the base-block 2 prevents any turning or twisting of said finger, and thus insures the maintenance of the projecting elastic end of the same in proper position for contact with the terminal on the head of the lamp.

While it is preferable, it is not essential to the broader embodiments of my invention that both of the flanges 4L and 5 of the metallic shell should be inwardly-bent fingers, as the flange which is secured to the base-block by the screw and nut might be a vertical one bearing against the side of the base-block-- as shown, for instance, at 5 in Fig. 6, the screw 6 engaging with a nut 7, let into a recess in the base-block, as there illustrated. Because of the laterally-proj ectin g screw,however, this construction is objectionable in cases where an outer casing is to be applied to the socket, and as one feature of my invention relates to such outer casing I always prefer to adopt the construction shown in Fig. 2.

The construction of the outer casing is shown in Fig. 3, 11 being the external tubular shell, of metal or other available material,

' 12 the cap-plate, and 13 a central internallythreaded nipple on said cap-plate. The shell 11 has a lining 14, of vulcanized fiber or other insulating material, and is internally flanged at the top, so as to overlap the cap-plate 12, to which the flange may be secured by soldering or brazing, or the cap-plate may be confined between the flange and the upper edge of the lining-sleeve. The nipple 13 is secured to the central portion of the cap-plate by riveting or otherwise, so that the casing comprises practically but a single piece,which can be applied, secured to, or removed from the socket as a unit. Surrounding and secured to the shell 11 is a ring 15, and through this thickened portion of the shell pass screws 16, whose inner ends enter sockets 17,fo'rmed in the sides of the base-block 2.

Having thus described my invention, I claim and desire to secure by Letters Patent 1. The combination in an electriclamp socket, of a base-block having a lateral recess in one side, with a metallic shell having an inwardly-bent flange engaging with said recess, an opposing flange, and means for securing said opposing flange to the base-block, substantially as specified.

2. The combination in an electric-lamp socket, of a base-block having a lateral recess in one side, with a metallic shell having an inwardly-bent flange engaging with said recess, an opposing flange, and means for securing said flange to the baseblock, said means serving as a binding-post for one of the conducting-Wires, substantially as specifled.

3. The combination in an electric-lamp socket, of the base-block having a lateral recess in one side of the same, a metallic shell having inwardly-projecting top flanges one of which engages With said recess, the other bearing against the under side of the block, and means for securing said second flange to the under side of the block, substantially as specified.

4. The combination in an electric-lamp socket, of the base-block having a transverse groove or recess therein, with a spring-finger having a portion contained in said recess and a projecting portion adapted to contact with the terminal on the head of the lamp, and a screw passing through the block and engaging with the spring-finger in the recess, the head of the said screw being on the back of the block and adapted to secure in place one of the conducting-wires, substantially as specified.

5. The combination in an electric-lamp socket, of a base-block having a lug projecting above the surface of the block on the back of the same, a metallic shell, and a spring contact-finger, with fastening -screws for said shell and finger also projecting above the back surface of the block on the opposite sides of the lug thereon, and serving to confine the conducting-wires, substantially as specified.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN D. PIERCE.

WVitnesses:

WILL. A. BARR, Jos. I'I. KLEIN. 

